welcome to you both. president obama pledged on september 12 to bring the killers to justice. siobhan, starting with you. how far along is the u.s. in the investigation, the kind of investigation to have to do that some >> they're fairly far along in terms of being able to identify some individuals through either tracking conversations or through video that is picked up. photographs and the like. so they have identified a number of individuals. they are trying to figure out now what the next steps are to deal with those individuals. much they've discovered that they hail from a number of different militant groups >> warner: you had a story today about an egyptian-born militant who was freed last year after the egyptian revolution from an egyptian prison >> right. he's a former egyptian islamic jihad operative. he was in the sights of the spy agencies prior to this attack that they have discovered that some of the militants in his network because he has set up these training camps in libya because you have more freedom of movement there have turned up as having taken, you know,